Julia Louis-Dreyfus explains Rolling Stone blunder

Julia Louis-Dreyfus has a perfectly good explanation for the mistake in the fake-tattoo of the Constitution supposedly tattooed on her back on the cover of the new Rolling Stone magazine.

The "Veep" actress says she was drunk ... and the John Hancock signature (he signed the Declaration of Independence, not the Constitution) is actually a birthmark.

"John Hancock not part of tattoo. It is a birthmark.1962 photo is proof. Apologies 2@RollingStone #crackexcuse," she wrote Thursday, with a spoof throwback image on Instagram of herself as a baby with "John Hancock" branded above just above her rear end.